CN109121098B

CN109121098B - Method and system for allocating channel

Info

Publication number: CN109121098B
Application number: CN201810975042.5A
Authority: CN
Inventors: 公维冰
Original assignee: BOE Technology Group Co Ltd
Current assignee: BOE Technology Group Co Ltd
Priority date: 2018-08-24
Filing date: 2018-08-24
Publication date: 2021-05-25
Anticipated expiration: 2038-08-24
Also published as: CN109121098A; US10917876B2; US20200068527A1

Abstract

The invention provides a method and a system for allocating channels, relates to the technical field of Internet of vehicles data broadcasting, and is used for solving the problem of low broadcast and data transmission efficiency of an MAC layer in an Internet of vehicles environment. A method of allocating channels, comprising: a first communication node in the Internet of vehicles determines a second communication node in the Internet of vehicles in a first channel allocation period, wherein the second communication node is a communication node except the first communication node in the communication range of the first communication node; and allocating s channels of the channels allowed to be allocated by the first communication node to s second communication nodes, wherein the channels allocated by different second communication nodes are different, s is the smaller value of n and m, n is the determined number of the second communication nodes, and m is the number of the channels allowed to be allocated by the first communication node.

Description

Method and system for allocating channel

Technical Field

The invention relates to the technical field of data broadcasting of internet of vehicles, in particular to a method and a system for allocating channels.

Background

With the development of information technology, the internet of things has become a hot problem of current research, and the internet of vehicles technology has been applied to our daily life.

In the internet of vehicles, limited by certain factors, the number and coverage of signal sources are limited, and there are inevitably weak signal areas or even no signal areas, and vehicles entering these areas generally connect to OBUs (On board units) of vehicles in strong signal areas in a self-organizing manner to receive signals sent by the signal sources. However, in the currently used WAVE (Wireless Access in Ve-high Environment) car networking protocol, an EDCA (enhanced Distributed Channel Access) mechanism is used to implement Channel allocation and service priority queuing, while EDCA uses a CSMA/CA (Carrier Multiple Access/connectivity Access) protocol to implement Channel Access, that is, only two nodes can communicate with each other in the same communication range at the same time, which results in low broadcast and data transmission efficiency of a Media Access Control (MAC) layer.

Disclosure of Invention

The embodiment of the invention provides a method and a system for allocating channels, which are used for solving the problem of low broadcast and data transmission efficiency of an MAC layer in an Internet of vehicles environment.

In order to achieve the above purpose, the embodiment of the invention adopts the following technical scheme:

in a first aspect, a method for allocating channels is provided, including: a first communication node in the Internet of vehicles determines a second communication node in the Internet of vehicles in a first channel allocation period, wherein the second communication node is a communication node except the first communication node in the communication range of the first communication node; and allocating s channels of the channels allowed to be allocated by the first communication node to s second communication nodes, wherein the channels allocated by different second communication nodes are different, s is the smaller value of n and m, n is the determined number of the second communication nodes, and m is the number of the channels allowed to be allocated by the first communication node.

Optionally, the method for allocating channels further includes: marking unallocated channels among channels allowed to be allocated by the first communication node as reserved channels in the first channel allocation period; and/or, in a second channel allocation period, when the second communication node detecting that the channel is allocated moves out of the communication range of the first communication node, marking the channel allocated to the second communication node as a reserved channel, wherein the second channel allocation period is any channel allocation period after the first channel allocation period; allocating the reserved channel to the second communication node of a currently unallocated channel during the second channel allocation period, wherein the second communication node of the currently unallocated channel includes: a second communication node detected to be within a communication range of the first communication node during the second channel allocation period; and/or the second communication node which does not allocate a channel in the last channel allocation period of the second channel allocation period.

Optionally, the determining a second communication node in the internet of vehicles in the first channel allocation period includes: broadcasting identity request information, wherein the identity request information is used for requesting an identity of a second communication node; receiving identity feedback information sent by the second communication node through a channel, and recording an identity of the second communication node contained in the received identity feedback information; and under the condition that at least two second communication nodes send the identity feedback information through the same channel, returning to the step of executing the broadcast identity request information until the condition that at least two second communication nodes send the identity feedback information through the same channel does not occur any more.

Optionally, the allocating s channels of the channels allowed to be allocated by the first communication node to s second communication nodes includes: and allocating channels to the second communication node in sequence from high to low according to the priority of the access class of the second communication node until the s channels are allocated.

Optionally, the allocating channels to the second communication node in sequence from high to low according to the priority of the access class of the second communication node until the s channels are allocated completely specifically includes: selecting a second communication node of a current channel to be allocated as a target node according to the sequence of the priority of the access class of the second communication node from high to low; selecting one channel from the channels allowed to be allocated by the first communication node to be allocated to the target node; identifying information fed back by the target node and representing that the currently allocated channel is suitable; under the condition that information which is fed back by the target node and is suitable for representing the currently allocated channel is not identified, reselecting one channel from the channels which are allowed to be allocated by the first communication node to be allocated to the target node until s channels are tried; and allocating channels to the next target node until s channels are allocated.

Optionally, the allocating s channels of the channels allowed to be allocated by the first communication node to s second communication nodes, further includes: and stopping allocating the channel to the second communication node of which the transmission opportunity reaches the maximum transmission time under the condition that the determined number n of the second communication nodes is greater than the number m of the channels allowed to be allocated by the first communication node.

Optionally, the method for allocating channels further includes: detecting whether the strength of a signal transmitted by the third communication node is lower than a threshold value; in the event that it is detected that the strength is below a threshold, performing the step of determining a second communication node in the Internet of vehicles within a first channel allocation period; wherein the third communication node is a communication node that allocates a channel for the first communication node.

Optionally, before the step of determining the second communication node in the internet of vehicles in the first channel allocation period is executed, the method further includes: detecting whether start communication information broadcasted by the third communication node is received, wherein the start communication information is used for informing the first node of starting broadcasting; and in the case of receiving the starting communication information, executing the step of determining a second communication node in the Internet of vehicles in the first channel allocation period.

In a second aspect, a system for allocating channels is provided, comprising: the node determination module is used for enabling a first communication node in the Internet of vehicles to determine a second communication node in the Internet of vehicles in a first channel allocation period, wherein the second communication node is a communication node except the first communication node in the communication range of the first communication node; and the channel dyeing module is configured to allocate s channels of the channels allowed to be allocated by the first communication node to s second communication nodes, where the channels allocated by different second communication nodes are different, s is a smaller value of n and m, n is the determined number of the second communication nodes, and m is the number of the channels allowed to be allocated by the first communication node.

Optionally, the system for allocating channels further includes: a channel marking module, configured to mark, in the first channel allocation period, an unallocated channel from among channels allowed to be allocated by the first communication node as a reserved channel; and/or, in a second channel allocation period, when the second communication node detecting that the channel is allocated moves out of the communication range of the first communication node, marking the channel allocated to the second communication node as a reserved channel, wherein the second channel allocation period is any channel allocation period after the first channel allocation period; the channel staining module is further configured to allocate, in the second channel allocation period, the reserved channel to the second communication node to which a channel is not currently allocated, where the second communication node to which a channel is not currently allocated includes: a second communication node detected to be within a communication range of the first communication node during the second channel allocation period; and/or the second communication node which does not allocate a channel in the last channel allocation period of the second channel allocation period.

Optionally, the node determining module is specifically configured to broadcast identity request information, where the identity request information is used to request an identity of a second communication node; receiving identity feedback information sent by the second communication node through a channel, and recording an identity of the second communication node contained in the received identity feedback information; and under the condition that at least two second communication nodes send the identity feedback information through the same channel, returning to the step of executing the broadcast identity request information until the condition that at least two second communication nodes send the identity feedback information through the same channel does not occur any more.

Optionally, the channel dyeing module is specifically configured to sequentially allocate channels to the second communication node from high to low according to the priority of the access class of the second communication node until s channels are allocated.

Optionally, the channel dyeing module is specifically configured to select, as a target node, a second communication node of a current channel to be allocated according to a sequence from high to low of an access class priority of the second communication node; selecting one channel from the channels allowed to be allocated by the first communication node to be allocated to the target node; identifying information fed back by the target node and representing that the currently allocated channel is suitable; under the condition that information which is fed back by the target node and is suitable for representing the currently allocated channel is not identified, reselecting one channel from the channels which are allowed to be allocated by the first communication node to be allocated to the target node until s channels are tried; and allocating channels to the next target node until s channels are allocated.

Optionally, the channel staining module is further configured to stop allocating a channel to the second communication node whose transmission opportunity reaches the maximum transmission time when the determined number n of the second communication nodes is greater than the number m of channels allowed to be allocated by the first communication node.

Optionally, the system for allocating channels further includes: the processing module is used for detecting whether the intensity of the signal transmitted by the third communication node is lower than a threshold value; determining, by the node determination module, a second communication node in the Internet of vehicles within a first channel allocation period if the strength is detected to be below a threshold; wherein the third communication node is a communication node that allocates a channel for the first communication node.

Optionally, the processing module is further configured to detect whether start communication information broadcasted by the third communication node is received, where the start communication information is used to notify the first communication node of starting broadcasting; and under the condition of receiving the communication starting information, determining a second communication node in the Internet of vehicles in a first channel allocation period through the node determination module.

In a third aspect, a computer-readable storage medium is provided, having stored therein instructions that, when run in a system for allocating channels, cause the system for allocating channels to perform the method for allocating channels according to the first aspect.

In a fourth aspect, there is provided a computer program product comprising instructions which, when run on a system for allocating channels, cause the system for allocating channels to perform the method for allocating channels according to the first aspect.

The embodiment of the invention provides a method and a system for allocating channels, which enable second communication nodes in the same communication range to adopt different channels to perform simultaneous data transmission on first communication nodes by performing channel allocation on the second communication nodes in the communication range of the first communication nodes. A plurality of channels can work simultaneously, compare and can only a channel work among the prior art, can solve and hide station, expose station and channel access fairness scheduling problem to the broadcast of MAC layer and data transmission's under the car networking environment efficiency has been improved. On the basis, the invention can also adopt a broadcast mechanism when sending the message.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a flowchart of a method for allocating channels according to an embodiment of the present invention;

fig. 2 is a schematic diagram of an allocation channel according to an embodiment of the present invention;

FIG. 3 is a diagram of an inter-frame relationship provided by an embodiment of the present invention;

fig. 4 is a communication relationship diagram between nodes according to an embodiment of the present invention;

fig. 5 is a diagram of a communication relationship between nodes according to another embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

An embodiment of the present invention provides a method for allocating channels, as shown in fig. 1, including:

s10, the first communication node in the Internet of vehicles determines a second communication node in the Internet of vehicles in the first channel allocation period, and the second communication node is a communication node except the first communication node in the communication range of the first communication node.

Here, the first communication node and the second communication node are not limited, and the first communication node and the second communication node may transmit signals via a certain protocol. For example, the first communication node and the second communication node may be at least one of an RSU (Road Side Unit) and an OBU (On board Unit), where the first communication node and the second communication node perform signal transmission through an 802.11 protocol, and the first communication node and the second communication node store the 802.11 protocol respectively.

The frame format of the signal interaction between the first communication node and the second communication node may use RTS/CTS (Request To Send/Clear To Send) frame format in 802.11 standard.

In some embodiments, step S10 specifically includes:

and S11, broadcasting identity request information, wherein the identity request information is used for requesting the identity of the second communication node.

That is, the first communication node sends the identity request information in a broadcast manner, and all the second communication nodes located in the communication range of the first communication node can receive the identity request information.

S12, receiving the identity feedback information sent by the second communication node through the channel, and recording the identity of the second communication node contained in the received identity feedback information.

That is, after receiving the identity request message sent by the first communication node, each second communication node may select one channel to reply identity feedback information to the first communication node, and at this time, the identity feedback information may be replied through a contention channel, but when a plurality of second communication nodes reply the identity feedback information through the same channel at the same time, the plurality of identity feedback information may collide, the first communication node may receive a signal generated by superimposing several second communication nodes, and the signal is unpredictable and decodable, so the first communication node may not recognize the identity feedback information of the several second communication nodes that reply the identity feedback information through the same channel, and the several second communication nodes may enter back-off at the same time. For the identity feedback information which is not collided, the first communication node can decode the information, and the first communication node records the identity of the corresponding second communication node after receiving the identity feedback information.

The identity feedback information may further include a channel used when the second communication node replies the identity feedback information, and the channel is preferentially allocated to the corresponding second communication node when the channel is allocated, or the portion of the channel recorded by the first communication node is preferentially used when the backoff-entering second communication node replies the identity feedback information next time, so as to reduce the probability of collision.

For how the second communication node knows that it needs to back off, for example, the first communication node broadcasts the identity feedback confirmation information, the second communication node that does not receive the identity feedback confirmation information is the second communication node that backs off, or other methods are adopted.

S13, under the condition that at least two second communication nodes send the identity feedback information through the same channel, the step of broadcasting the identity request information is returned to be executed until the condition that at least two second communication nodes send the identity feedback information through the same channel does not occur any more.

That is, the steps S11 and S12 need to be repeated for the second communication node entering the backoff until the situation that at least two second communication nodes send the identity feedback information through the same channel does not occur (no message collision occurs). If the case where at least two second communication nodes transmit the identity feedback information through the same channel does not occur when the steps S11 and S12 are performed for the first time, the step S13 does not need to be performed.

Here, as to how to avoid the problem of repeated reception of the identity feedback information when steps S11 and S12 are repeatedly executed, for example, each time step S11 is executed, the identity request information broadcast by the first communication node is the same, but the second communication node whose identity has been recorded by the first communication node does not reply with the identity feedback information any more. Alternatively, each time step S11 is executed, the identity request information broadcast by the first communication node is different, and the second communication node whose identity has been recorded by the first communication node does not receive the new identity request information. It may also be the identity request information that can be received by the second communication node that has been registered with the identity by the first communication node, but the identity request information indicates that it does not need to reply with the identity feedback information. Or in any other way, the embodiments of the present invention are not limited to this.

In addition, for the case how to determine that at least two second communication nodes do not send the identity feedback information through the same channel, for example, the case may be that no identity feedback information is received within a set time or the first communication node does not receive any information that cannot be identified.

As described above, the frame format used for the identity request information and the identity feedback information is not limited, and may be, for example, a BRTS/BCTS (broadcast request to send/broadcast clear to send) frame format, which is specifically shown in table 1 and table 2.

TABLE 1 frame format for BRTS

TABLE 2 frame format of BCTS

The BRTS and BCTS structures in table 1 and table 2 are the same, where BRTS Control (BRTS Control field) and BCTS Control (BCTS Control field) in Frame Control (Frame Control field) in MAC header are used to define information such as protocol version, Frame type, fragmentation, retry number, Duration (Duration) indicates approximate back-off time of the second node in which collision occurs, RA indicates a receiving station address (generally, MAC address), TA indicates a transmitting station address (generally, MAC address), and FCS is a Frame check field. The CH is an added domain and indicates a channel allocated by the first communication node to the second communication node.

And S20, allocating S channels of the channels allowed to be allocated by the first communication node to S second communication nodes, wherein the channels allocated by different second communication nodes are different, S is the smaller value of n and m, n is the determined number of the second communication nodes, and m is the number of the channels allowed to be allocated by the first communication node.

Wherein, the number n of the second communication nodes may be larger than the number m of channels allowed to be allocated by the first communication node according to the density degree of the vehicle, in which case, s is m; the number n of second communication nodes may also be less than the number m of channels allowed to be allocated by the first communication node, in which case s-n; the number n of second communication nodes may also be equal to the number m of channels the first communication node is allowed to allocate, in which case s-m or s-n.

The channel allowed to be allocated by the first communication node refers to a channel which is not occupied, for example, a processing module inside the first communication node learns which channels are allowed to be allocated by the first communication node according to the use condition of the channels, and after the channels are allocated by the first communication node, no collision occurs when the messages are transmitted. The number p of the channels which can be allocated by each first communication node at most is the same, and the specific value of p is not limited herein, but the number m of the channels which can be allocated by different first communication nodes is not completely the same.

Here, the number p of channels assignable by the first communication node at most is taken as 7 as an example, and as shown in fig. 2, the RSU is a first-stage first communication node, the number m of channels allowed to be assigned when assigning channels is taken as 7, and the RSU is channel 1, channel 2, channel 3, channel 4, channel 5, channel 6, and channel 7, and the number n of second communication nodes is taken as 2, and the RSU is OBU1 and OBU2, respectively. At this time, S is 2, the RSU may arbitrarily select two of seven channels to be allocated to the OBU1 and the OBU 2. For example, channel 5 is allocated to the OBU1 and channel 7 is allocated to the OBU 2. The OBU1 is the first communication node of the second level, since the channel 5 is already allocated by the first communication node of the first level for transmitting information between the RSU and the OBU1, the number m of channels that the OBU1 allows to allocate when allocating channels is 6, respectively channel 1, channel 2, channel 3, channel 4, channel 6, channel 7, and the number n of second communication nodes is 3, the OBU1 selects to allocate channel 6 to the OBU3, channel 1 to the OBU10, and channel 2 to the OBU 9. Similarly, the OBU2 is the first communication node in the second level, the number of allowed channels m is 6, which is channel 1, channel 2, channel 3, channel 4, channel 5, and channel 6, the number of second communication nodes n is 1, and the OBU2 selects channel 4 to be allocated to the OBU 3. The OBU3 is the first communication node of the third level, since the channel 4 has been allocated by the second level first communication node for transmitting information between the OBU2 and the OBU3, and since the channel 6 has been allocated by the second level first communication node for transmitting information between the OBU1 and the OBU3, the number m of channels allowed to be allocated by the OBU3 when allocating channels is 5, which are channel 1, channel 2, channel 3, channel 5, and channel 7, respectively, and the number n of second communication nodes is 3, the OBU3 selects to allocate channel 3 to the OBU4, channel 7 to the OBU5, and channel 5 to the OBU 6.

Therefore, the first communication node can only allocate an unoccupied channel to a second communication node within its communication range, and the second communication node is likely to be the first communication node of the next stage. When the second communication node is used as the first communication node of the next level, the first communication node of the current level of the channel which is already allocated by the first communication node of the previous level has no allocation right. The specific allocation principle is not limited herein, and for example, the channel may be allocated to the second communication node according to the sequence of receiving the identity feedback information, or the channel may be allocated to the second communication node according to the signal strength degree of receiving the identity feedback information, or other realizable manners.

Based on this, taking the OBU1 as an example, the communication range of the OBU1 includes the OBU3, the OBU9, and the OBU10, and after the channel is allocated by using the method for allocating a channel provided by the embodiment of the present invention, the processes of the OBU1 communicating with the OBU3 through the channel 6, the OBU1 communicating with the OBU9 through the channel 2, and the OBU1 communicating with the OBU10 through the channel 1 can be completed at the same time. In the prior art, only two nodes can communicate at a time in the same communication range, namely, only after the OBU1 and the OBU3 are communicated, the OBU1 and the OBU9 are communicated, and then the OBU1 and the OBU10 are communicated. Compared with the prior art, the embodiment of the invention can obviously improve the efficiency of data transmission.

In some embodiments, in order to ensure fast transmission of the emergency message, the first communication node allocates channels to the second communication node in sequence from the highest priority to the lowest priority of the access class of the second communication node until s channels are allocated.

That is, after receiving all the identity feedback information sent by the second communication node, the first communication node first allocates a channel to the second communication node with a high AC (Access Category) priority. The AC priority ordering may refer to the ordering in the 802.11 protocol, and is exemplarily divided into four priority queues of AC-Voice (Voice stream), AC-Video (Video stream), AC-Best-effort (Best-effort stream), and AC-Back-group (background stream) in order of priority from high to low, and the second communication node of the higher priority queue has higher ability to seize the channel. Or adds AC-Traffic safety as the highest priority information. The traffic safety stream may include traffic accident information, road congestion information, road closure information, and other traffic related information, for example. According to the principle of priority, when a new second communication node is added in the communication range of a first communication node during the movement of a vehicle, as long as the AC priority of the newly added second communication node is high, even if other second communication nodes still wait for the first communication node to allocate a channel, the first communication node still allocates the channel to the second communication node with high priority.

Here, the channel is used as much as possible to transmit the AC with the high priority, so that when the channel is not allocated to the second communication node having the AC with the high priority, and the channel is idle, the channel that the first communication node can be allowed to allocate may be preempted, where the channel contention employs a Distributed Coordination Function (DCF). If there are no other higher priority ACs, then the second communication node will use the assigned channel. Second communication nodes which are not allocated with channels cannot arbitrarily send messages until the first communication nodes inform that the first communication nodes can send messages, the first communication nodes send a specified channel rule to each second communication node through a competition channel, the second communication nodes which are allocated with channels can be called determined channel nodes, and the second communication nodes which are not allocated with channels can be called nondeterministic channel nodes.

Based on the periodic broadcast of the first communication nodes, a relatively fixed multi-channel simultaneous transmission mechanism is established between the first communication nodes and the second communication nodes, so that when each first communication node broadcasts messages again, such as messages with high real-time requirements, such as traffic safety, road accidents, voice and the like, the second communication nodes basically do not need to carry out window back-off or competition channels and can directly send the messages through the channels when the number of the second communication nodes in the communication range of the first communication nodes is smaller than the number of the channels allowed to be allocated by the first communication nodes. For non-real-time messages, the method basically saves competition time and improves the forwarding efficiency.

In some embodiments, sequentially allocating channels to the second communication node from high to low according to the priority of the access class of the second communication node until s channels are allocated, specifically including:

s21, selecting the second communication node of the current channel to be distributed as the target node according to the order of the priority of the access class of the second communication node from high to low.

Here, the channels are assigned to the second communication nodes in order of the priority of the access class, and one second communication node is assigned to the next communication node after the assignment is completed.

S22, selecting one channel from the channels allowed to be allocated by the first communication node to be allocated to the target node.

Here, one of the channels to be allocated by the first communication node may be arbitrarily selected, and the number of the channels to be allocated by the first communication node is allowed to be smaller and smaller as the channels are allocated.

And S23, identifying the information which is fed back by the target node and is suitable for the currently distributed channel.

Illustratively, if the target node is using a currently allocated channel, the currently allocated channel is deemed unsuitable. That is, if another first communication node uses the same channel as the currently allocated channel to communicate with the target node, the target node determines that the currently allocated channel is not suitable, and if another first communication node uses the same channel as the currently allocated channel to communicate with the target node but the communication relationship between the two is eliminated, the target node is considered not to use the currently allocated channel and the currently allocated channel is suitable. Of course, other factors may also be considered in combination.

That is, after the first communication node allocates the channel to the target node, the target node feeds back information to the first communication node, and if the allocated channel is not suitable, S24 is executed, and if the allocated channel is suitable, the process directly proceeds to S25.

Here, the target node may feed back information to the first communication node when it is determined that the currently allocated channel is suitable, and may not feed back information when the currently allocated channel is not suitable. If the first communication node does not receive the feedback information, it indicates that the information indicating that the currently allocated channel is suitable, which is fed back by the target node, is not recognized, and it is necessary to re-allocate a channel to the target node, and S24 is performed. If the first communication node receives the feedback information, it indicates that the information indicating that the currently allocated channel is suitable, which is fed back by the target node, is identified, and the channel does not need to be reallocated, and S25 is performed.

The target node may also feed back information to the first communication node when determining that the currently allocated channel is not suitable, and not feed back information when the currently allocated channel is suitable. If the first communication node receives the feedback information, it indicates that the information indicating that the currently allocated channel is suitable, which is fed back by the target node, is not identified, and it is necessary to re-allocate a channel to the target node, and S24 is performed. If the first communication node does not receive the feedback information, it indicates that the information indicating that the currently allocated channel is suitable, which is fed back by the target node, is identified, and the channel does not need to be reallocated, and S25 is performed.

Of course, other approaches are possible.

Wherein, the feedback information is necessarily the type of information that the first communication node can recognize.

And S24, under the condition that the information which is fed back by the target node and is suitable for representing the currently allocated channel is not identified, reselecting one channel from the channels which are allowed to be allocated by the first communication node to be allocated to the target node until S channels are tried.

That is, if the reallocated channels are suitable, the process proceeds to S25, and if S channels are tried and have not been allocated to suitable channels, the process proceeds to S25, and a channel is allocated to the second communication node after an idle channel is available, and since the second communication node has a higher priority of access class, the channel is preferentially allocated to the second communication node.

And S25, allocating channels to the next target node until S channels are allocated.

I.e., loop S21-S24 until S channels are allocated.

In the channel allocation process, the node B may be used as the second communication node of the node a or the second communication node of the node C, and at this time, if the node a and the node C transmit signals to the node B through the channel 5 at the same time, the messages may collide, which affects the transmission effect. Therefore, in order to avoid the above situation, in the embodiments of the present invention, after receiving the channel allocated by the first communication node, the second communication node determines whether the currently allocated channel is reasonable, if so, replies a confirmation message to the first communication node, and if not, the first communication node reallocates the channel to the second communication node, so as to improve the accuracy of channel allocation.

In some embodiments, in the case that the determined number n of second communication nodes is greater than the number m of channels allowed to be allocated by the first communication node, the allocation of channels to the second communication nodes whose transmission opportunities have reached the maximum transmission time is stopped.

In the case where the determined number n of second communication nodes is equal to or less than the number m of channels allowed to be allocated by the first communication node, each of the second communication nodes can be allocated with a channel, and therefore, it is not necessary to consider whether or not it is necessary to stop allocating channels to some of the second communication nodes. However, in the case that the determined number n of second communication nodes is greater than the number m of channels allowed to be allocated by the first communication node, at least one second communication node is waiting for the first communication node to allocate a channel, and therefore, for the second communication node whose transmission opportunity reaches the maximum transmission time (TXOP Limit), the allocation of a channel thereto may be stopped, and a corresponding channel may be allocated to the waiting second communication node.

In some embodiments, in order to ensure consistency of channel allocation and avoid channel allocation errors, unallocated channels among channels allowed to be allocated by the first communication node are marked as reserved channels in the first channel allocation period; and/or marking the channel allocated to the second communication node as a reserved channel under the condition that the second communication node detecting the allocated channel moves out of the communication range of the first communication node in the second channel allocation period, wherein the second channel allocation period is any channel allocation period after the first channel allocation period.

And allocating a reserved channel to a second communication node which is not allocated with the channel currently in a second channel allocation period, wherein the second communication node which is not allocated with the channel currently comprises: a second communication node detected to enter the communication range of the first communication node in the second channel allocation period; and/or a second communication node that has not allocated a channel during a last channel allocation period of the second channel allocation period.

Here, "and/or" is only one kind of association relation describing an associated object, and means that there may be three kinds of relations, for example, a and/or B, which may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.

The above channel allocation rule is adopted for message transmission between the first communication node and the second communication node, the first communication node periodically determines that the second communication node is within the communication range of the first communication node, for example, the first communication node broadcasts identity request information, and the second communication node transmits identity feedback information. The first communication node senses the departure of the first communication node by receiving the identity feedback information, if a second communication node with an allocated channel moves out of the communication range of the first communication node and a second communication node without the allocated channel still exists, the first communication node allocates the channel to the second communication node without the allocated channel. Otherwise, these channels are reserved.

When a second communication node enters the communication range of the first communication node, the second communication node receives the identity request information periodically sent by the first communication node, and then the second communication node sends identity feedback information to the first communication node through a contention channel. The first communication acquires the joining of the new second communication node by receiving the identity feedback information, checks whether a reserved channel exists, and if so, allocates the channel to the new second communication node, otherwise, the second communication node is used as a non-determined channel node.

Here, the channels of the first communication node and each of the second communication nodes do not interfere with each other, and the channels are one edge, not one face, like a connecting line between two points, and therefore, a process of allocating a channel to a second communication node by the first communication node is called edge-colored channel allocation of the first communication node and the second communication nodes around the first communication node. These channels can transmit data simultaneously, so the more channels, the higher the transmission efficiency obviously, and then the control channel can also be used as the data channel, since the current car networking mainly adopts 7-channel mode, i.e. the mode of 1 control channel +6 service channels, which can be called 7-dye channel allocation.

The 1609.4 standard in the WAVE protocol does not present an effective broadcast strategy, where a side-dyeing broadcast mechanism is proposed based on 7-dyeing channel assignment. Wherein 7 channels represent 7 colors, each first communication node dyes its communication link with the second communication node with 7 colors, and the link colors in the adjacent communication ranges cannot be the same, whereby the 7 channels are differentially assigned.

By adopting the BRTS broadcasting mechanism, each second communication node accessing the Internet through one first communication node can receive the BRTS, and meanwhile, the first communication node in the self-organizing network area carries out channel distribution based on a 7-dyeing channel distribution rule to establish a 7-dyeing broadcasting network. Each first communication node then internally stores a channel staining list, as in table 3, which specifies the channel assignments around the ad hoc node. The transmission channel of the non-deterministic channel node is not determined and needs to wait for the notification of other first communication nodes.

Table 3 channel staining list

Second communication node address	Channel number	Whether to determine a channel
			Address 1	Channel 1	Is that
Address 2	Channel 2	Is that
			Address 3	Channel 3	Is that
……	……	Is that
			Address 7	Channel 7	Is that
Address 8		Whether or not
			……	……	Whether or not
Address n		Whether or not

In channel coloring broadcast, channel allocation may be divided into at least two time periods, a first channel allocation period and a second channel allocation period.

The first channel allocation period represents that the dyed channels in the channel dyeing list are adopted for direct access, and the second channel allocation period represents that the non-certain channel nodes compete for the channels. The first channel allocation period may be regarded as a temporary central point controlled central coordination function (PCF), wherein the first communication node is called a temporary central point, and the backoff start time in the CAMS/CA (Carrier Sense Multiple Access with connectivity Access/Collision Avoidance) protocol is called a temporary central frame interval (TPIFS), as shown in fig. 3, other periods are the same as those in the prior art, and are not described herein again.

As shown in fig. 4 (a), the dotted circle represents the detection range of the node, and the solid circle represents the communication range of the node. If node A wants to send information to node B, node A listens first, node A finds that there is node B in its own transmission range and can send information, but node A does not have node C in its listening range, so node A does not know that node C is sending information to node B, and then node A sends information to node B, and node C as a hidden node also sends information to node B. At this time, the node B receives the information transmitted by the node a and the node C at the same time. In the prior art, only one channel can be used for sending information, the channels are the same, and the frequency ranges of the messages are also the same, so that the frequency ranges of the messages sent by the node A and the node C to the node B are the same, the messages in the same frequency range are overlapped, the node B cannot identify the overlapped messages, and the problem of hidden stations is caused due to collision and transmission failure of the messages.

In the present invention, by dyeing channel allocation, as shown in (B) of fig. 4, if a node B is used as a first communication node, in the channel allocation process, the node B allocates different channels to a node a and a node C within its communication range, respectively; if node B is used as both the second communication node of node a and the second communication node of node C, after node a allocates channel 1 to node B in the channel allocation process, and the communication between the two is normal, if node C also allocates channel 1 to node B, node B will feed back information indicating that channel 1 is not suitable, so that node C allocates a channel other than channel 1 to node B. Such that communication between node B and node a uses a different channel than communication between node B and node C. Based on this, in the communication process, the node A sends information to the node B through the channel 1, the node C sends information to the node B through the channel 2, and the messages sent by the node A and the node C belong to different frequency ranges, so the node B can simultaneously access the information sent by the node A and the node C in the communication range through two different channels, thereby avoiding the problem of hidden stations.

As shown in fig. 5 (a), the dotted circle represents the detection range of the node, and the solid circle represents the communication range of the node. In the prior art, when a node C uses a channel to send information to a node D, a node B has information to transmit to the node a, but the node C is located within a detection range of the node B, the node B detects that the node C uses the channel, and the node C is an exposed node, so the node B backs up and does not transmit information to the node a, which causes a station exposure problem. And the node B does not reply to the information sent by the node a, so that the node a also enters back-off when failing to transmit, and the contention window is continuously increased, so that the node a waits, cannot complete the message transmission between the node a and the node B, and the fairness problem is caused.

In the invention, by means of channel allocation with edge coloring, as shown in (B) in fig. 5, a node B detects that a node C is sending information to a node D by using a channel 2, and by means of channel coloring, the node B selects a channel (for example, a channel 1) other than the channel 2 to perform mutual information transmission with the node a, and the node C sends information to the node D through the channel 2 and simultaneously the node B sends information to the node a through the channel 1, and the node B does not need to enter back-off, thereby well solving the problem of station exposure. In addition, because the message transmission between the node A and the node B does not need to wait until the message transmission of the node C and the node D is finished, the adopted channels are different, the condition that the transmission of the node A fails does not occur any more, and the problem of fairness is well solved.

In the invention, when the first communication node sends the message, the first communication node carries out channel allocation on the second communication node in the communication range, so that the second communication nodes in the same communication range adopt different channels to carry out simultaneous data transmission. A plurality of channels can work simultaneously, compare and can only a channel work among the prior art, can solve and hide station, expose station and channel access fairness scheduling problem to the broadcast of MAC layer and data transmission's under the car networking environment efficiency has been improved. On the basis, the invention can also adopt a broadcast mechanism when sending the message.

In some embodiments, the method of allocating channels further comprises:

detecting whether the strength of a signal transmitted by the third communication node is lower than a threshold value; in the case that the detected intensity is lower than the threshold value, executing the step of determining a second communication node in the internet of vehicles in the first channel allocation period; wherein the third communication node is a communication node that allocates a channel for the first communication node.

That is, when the first communication node detects that the strength of the signal transmitted thereto by the third communication node is lower than the threshold, the first communication node starts to operate as a channel broadcast of the next stage, where the first communication node is the next stage of the third communication node, similarly to the OBU1 and the OBU3 in fig. 2.

In the car networking, each RSU can periodically broadcast the BRTS to its communication range, and each second communication node receiving the BRTS checks the strength of the signal between itself and the first communication node, and if the strength is lower than a certain threshold (the threshold is determined by the transmission quality of the second communication node), it then broadcasts the BRTS (as the first communication node of the next level) so that the second communication nodes around it through the self-organizing access RSU can receive the BRTS. Then, the first communication node at the next stage broadcasts the BRTS to a second communication node which is further away, and so on, until all the communication nodes accessing the Internet through the RSU all receive the BRTS. Here, each second communication node accesses the internet through only one RSU, and stores the MAC address of this RSU. In addition, in order to avoid repeated reception of the BRTS, each ad hoc second communication node sets a timer upon receiving a BRTS, and does not receive the broadcast packet of the RSU any more during the time, and the time value of the timer needs to be specifically set according to the specific network environment.

In some embodiments, detecting whether the strength of the signal transmitted by the third communication node is below a threshold; under the condition that the detected intensity is lower than the threshold value, detecting whether starting communication information broadcasted by the third communication node is received or not, wherein the starting communication information is used for informing the first communication node of starting broadcasting; and in case of receiving the start communication information, performing the step of determining a second communication node in the vehicle networking within the first channel allocation period.

That is, the first communication node performs communication after receiving the instruction to start communication transmitted from the upper stage.

The BRTS used for broadcasting stores therein the address of the first communication node for distinguishing which first communication node is performing channel coloring. In order to avoid too many BRTS broadcasts causing too many collisions, embodiments of the present invention limit the speed of the broadcasts based on the density of the vehicles. That is, when the density of vehicles is high, it is possible to select to use the point-by-point broadcast BRTS, and each time a first communication node is broadcast, the first communication node does not immediately broadcast the BRTS but waits for the third communication node broadcast thereto to transmit a message notifying the broadcast thereof. When the vehicles are sparse, the first communication node can be broadcasted immediately by probability selection, or the broadcasting time can be selectively regulated according to the surrounding vehicle density.

The embodiment of the invention provides a system for distributing channels, which comprises: and the node determination module is used for enabling a first communication node in the Internet of vehicles to determine a second communication node in the Internet of vehicles in the first channel allocation period, wherein the second communication node is a communication node except the first communication node in the communication range of the first communication node.

And the channel dyeing module is used for allocating s channels in the channels allowed to be allocated by the first communication node to s second communication nodes, wherein the channels allocated by different second communication nodes are different, s is the smaller value of n and m, n is the determined number of the second communication nodes, and m is the number of the channels allowed to be allocated by the first communication node.

In the channel allocation system provided in the embodiment of the present invention, the channel dyeing module performs channel allocation on the second communication node within the communication range of the first communication node, so that the second communication node within the same communication range performs simultaneous data transmission on the first communication node using different channels. A plurality of channels can work simultaneously, compare and can only a channel work among the prior art, can solve and hide station, expose station and channel access fairness scheduling problem to the broadcast of MAC layer and data transmission's under the car networking environment efficiency has been improved. On the basis, the invention can also adopt a broadcast mechanism when sending the message.

In some embodiments, the system for allocating channels further comprises a channel marking module, configured to mark, in a first channel allocation period, an unallocated channel from among channels allowed to be allocated by the first communication node as a reserved channel; and/or marking the channel allocated to the second communication node as a reserved channel under the condition that the second communication node detecting the allocated channel moves out of the communication range of the first communication node in the second channel allocation period, wherein the second channel allocation period is any channel allocation period after the first channel allocation period.

The channel staining module is further configured to allocate a reserved channel to a second communication node that is not currently allocated with a channel in a second channel allocation period, where the second communication node that is not currently allocated with a channel includes: a second communication node detected to enter the communication range of the first communication node in the second channel allocation period; and/or a second communication node that has not allocated a channel during a last channel allocation period of the second channel allocation period.

Here, by updating the address information of the second communication node and the information of the reserved channel and continuously performing channel allocation, a relatively fixed multi-channel simultaneous transmission mechanism can be established between the first communication node and the second communication node.

In some embodiments, the node determining module is specifically configured to broadcast identity request information, where the identity request information is used to request an identity of the second communication node.

And receiving the identity feedback information sent by the second communication node through the channel, and recording the identity of the second communication node contained in the received identity feedback information.

And under the condition that at least two second communication nodes send the identity feedback information through the same channel, returning to the step of executing the broadcast identity request information until the condition that at least two second communication nodes send the identity feedback information through the same channel does not occur any more.

In order to ensure that important information is transmitted preferentially, in some embodiments, the channel dyeing module is specifically configured to allocate channels to the second communication node in sequence from high to low in priority of an access class of the second communication node until s channels are allocated.

In some embodiments, the channel staining module is further configured to stop allocating channels to the second communication node whose transmission opportunity reaches the maximum transmission time if the determined number n of second communication nodes is greater than the number m of channels allowed to be allocated by the first communication node.

In order to improve the transmission quality of information and avoid the problem that the signal is delayed due to the fact that part of second communication nodes are too long in waiting time, the second communication nodes with the transmission opportunities reaching the maximum sending time are stopped from being allocated with channels to vacate the channels.

In some embodiments, the system for allocating channels further comprises: the processing module is used for detecting whether the intensity of the signal transmitted by the third communication node is lower than a threshold value; under the condition that the strength is detected to be lower than the threshold value, determining a second communication node in the Internet of vehicles in the first channel allocation period through a node determination module; wherein the third communication node is a communication node that allocates a channel for the first communication node.

Here, the second communication node farther from the first communication node is used as the first communication node at the next stage, so that the peripheral OBUs can all receive the BRTS, thereby increasing the range of signal transmission.

In some embodiments, the processing module is further configured to detect whether start communication information broadcasted by the third communication node is received, and the start communication information is used to inform the first communication node of starting broadcasting.

And under the condition of receiving the communication starting information, determining a second communication node in the Internet of vehicles in the first channel allocation period through the node determination module.

According to the embodiment of the invention, the broadcasting speed is limited according to the density of the vehicles, namely, when the density of the vehicles is high, the point-by-point broadcasting BRTS can be selected, and when the first communication node broadcasts the BRTS, the first communication node does not broadcast the BRTS immediately, but waits for the third communication node which broadcasts the BRTS to send a message to inform the third communication node of the BRTS to broadcast the BRTS, so that the too many collisions caused by too many BRTS broadcasts are avoided.

An embodiment of the present invention further provides a computer-readable storage medium, where instructions are stored in the computer-readable storage medium, and when the instructions are executed in a system for allocating channels, the system for allocating channels is enabled to execute the method for allocating channels.

Embodiments of the present invention further provide a computer program product containing instructions, which when run on a system for allocating channels, causes the system for allocating channels to execute the above method for allocating channels.

Through the description of the above embodiments, it is clear to those skilled in the art that, for convenience and simplicity of description, the foregoing division of the functional modules is merely used as an example, and in practical applications, the foregoing function distribution may be completed by different functional modules according to needs, that is, the internal structure of the system may be divided into different functional modules to complete all or part of the above described functions.

In the several embodiments provided in the present application, it should be understood that the disclosed system and method may be implemented in other ways. For example, the above-described system embodiments are merely illustrative, and for example, the division of the modules or units is only one logical division, and there may be other divisions when actually implemented, for example, a plurality of units or components may be combined or may be integrated into another system, or some features may be omitted, or not executed.

In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a readable storage medium. Based on such understanding, the technical solution of the embodiments of the present invention may be essentially or partially contributed to by the prior art, or all or part of the technical solution may be embodied in the form of a software product, where the software product is stored in a storage medium and includes several instructions to enable a device (which may be a single chip, a chip, or the like) or a processor (processor) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: various media capable of storing program codes, such as a usb disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.

Claims

1. A method for allocating channels, comprising:

a first communication node in the Internet of vehicles determines a second communication node in the Internet of vehicles in a first channel allocation period, wherein the second communication node is a communication node except the first communication node in the communication range of the first communication node;

allocating s channels of the channels allowed to be allocated by the first communication node to s second communication nodes, wherein the channels allocated by different second communication nodes are different, s is the smaller value of n and m, n is the determined number of the second communication nodes, and m is the number of the channels allowed to be allocated by the first communication node;

any one of the second communication nodes which obtain the distribution channel is used as a first communication node of the next level, and the channel which can be distributed by the first communication node of the next level is as follows: and the other assignable channels are except the channels of the first communication node for communicating with the first communication node of the next stage.

2. The method for allocating channels according to claim 1, further comprising:

marking unallocated channels among channels allowed to be allocated by the first communication node as reserved channels in the first channel allocation period; and/or, in a second channel allocation period, when the second communication node detecting that the channel is allocated moves out of the communication range of the first communication node, marking the channel allocated to the second communication node as a reserved channel, wherein the second channel allocation period is any channel allocation period after the first channel allocation period;

allocating the reserved channel to the second communication node of a currently unallocated channel during the second channel allocation period, wherein the second communication node of the currently unallocated channel includes: a second communication node detected to be within a communication range of the first communication node during the second channel allocation period; and/or the second communication node which does not allocate a channel in the last channel allocation period of the second channel allocation period.

3. The method of allocating channels according to claim 1, wherein said determining the second communication node in the internet of vehicles during the first channel allocation period comprises:

broadcasting identity request information, wherein the identity request information is used for requesting an identity of the second communication node;

receiving identity feedback information sent by the second communication node through a channel, and recording an identity identifier of the second communication node contained in the received identity feedback information;

4. The method according to claim 1, wherein said allocating s channels of the channels allowed to be allocated by the first communication node to s second communication nodes comprises:

and allocating channels to the second communication node in sequence from high to low according to the priority of the access class of the second communication node until the s channels are allocated.

5. The method for allocating channels according to claim 4, wherein the allocating channels to the second communication node in order from a high priority to a low priority of the access class of the second communication node until s channels are allocated completely specifically comprises:

selecting a second communication node of a current channel to be allocated as a target node according to the sequence of the priority of the access class of the second communication node from high to low;

selecting one channel from the channels allowed to be allocated by the first communication node to be allocated to the target node;

identifying information fed back by the target node and representing that the currently allocated channel is suitable;

under the condition that information which is fed back by the target node and is suitable for representing the currently allocated channel is not identified, reselecting one channel from the channels which are allowed to be allocated by the first communication node to be allocated to the target node until s channels are tried;

and allocating channels to the next target node until s channels are allocated.

6. The method of allocating channels according to claim 4, wherein said allocating s channels of the channels allowed to be allocated by the first communication node to s second communication nodes, further comprises:

and stopping allocating the channel to the second communication node of which the transmission opportunity reaches the maximum transmission time under the condition that the determined number n of the second communication nodes is greater than the number m of the channels allowed to be allocated by the first communication node.

7. The method for allocating channels according to claim 1, further comprising:

detecting whether the strength of a signal transmitted by the third communication node is lower than a threshold value; in the event that it is detected that the strength is below a threshold, performing the step of determining a second communication node in the Internet of vehicles within a first channel allocation period;

wherein the third communication node is a communication node that allocates a channel for the first communication node.

8. The method of allocating channels according to claim 7, wherein prior to performing said step of determining a second communication node in said internet of vehicles during a first channel allocation period, said method further comprises:

detecting whether start communication information broadcasted by the third communication node is received, wherein the start communication information is used for informing the first communication node of starting broadcasting;

and in the case of receiving the starting communication information, executing the step of determining a second communication node in the Internet of vehicles in the first channel allocation period.

9. A system for allocating channels, comprising:

the node determination module is used for enabling a first communication node in the Internet of vehicles to determine a second communication node in the Internet of vehicles in a first channel allocation period, wherein the second communication node is a communication node except the first communication node in the communication range of the first communication node;

a channel dyeing module, configured to allocate s channels of the channels allowed to be allocated by the first communication node to s second communication nodes, where the channels allocated by different second communication nodes are different, s is a smaller value of n and m, n is the determined number of the second communication nodes, and m is the number of the channels allowed to be allocated by the first communication node;

10. The system for allocating channels according to claim 9, further comprising:

a channel marking module, configured to mark, in the first channel allocation period, an unallocated channel from among channels allowed to be allocated by the first communication node as a reserved channel; and/or, in a second channel allocation period, when the second communication node detecting that the channel is allocated moves out of the communication range of the first communication node, marking the channel allocated to the second communication node as a reserved channel, wherein the second channel allocation period is any channel allocation period after the first channel allocation period;

the channel staining module is further configured to allocate, in the second channel allocation period, the reserved channel to the second communication node to which a channel is not currently allocated, where the second communication node to which a channel is not currently allocated includes: a second communication node detected to be within a communication range of the first communication node during the second channel allocation period; and/or the second communication node which does not allocate a channel in the last channel allocation period of the second channel allocation period.

11. The system according to claim 9, wherein the node determining module is configured to broadcast an identity request message, where the identity request message is used to request an identity of the second communication node;

receiving identity feedback information sent by the second communication node through a channel, and recording an identity of the second communication node contained in the received identity feedback information;

12. The system according to claim 9, wherein the channel staining module is specifically configured to assign channels to the second communication node in sequence from high to low according to the priority of the access class of the second communication node until s channels are assigned.

13. The system for allocating channels according to claim 12, wherein the channel staining module is specifically configured to select, as a target node, a second communication node of a channel to be currently allocated according to an order from a high priority to a low priority of an access class of the second communication node; selecting one channel from the channels allowed to be allocated by the first communication node to be allocated to the target node;

identifying information fed back by the target node and representing that the currently allocated channel is suitable; under the condition that information which is fed back by the target node and is suitable for representing the currently allocated channel is not identified, reselecting one channel from the channels which are allowed to be allocated by the first communication node to be allocated to the target node until s channels are tried;

and allocating channels to the next target node until s channels are allocated.

14. The system according to claim 12, wherein the channel staining module is further configured to stop allocating channels to the second communication node whose transmission opportunity reaches the maximum transmission time if the determined number n of the second communication nodes is greater than the number m of channels allowed to be allocated by the first communication node.

15. The system for allocating channels according to claim 9, further comprising:

the processing module is used for detecting whether the intensity of the signal transmitted by the third communication node is lower than a threshold value; determining, by the node determination module, a second communication node in the Internet of vehicles within a first channel allocation period if the strength is detected to be below a threshold;

16. The system according to claim 15, wherein the processing module is further configured to detect whether start communication information broadcasted by the third communication node is received, the start communication information being used to notify the first communication node to start broadcasting;

and under the condition of receiving the communication starting information, determining a second communication node in the Internet of vehicles in a first channel allocation period through the node determination module.

17. A computer readable storage medium having instructions stored thereon, which when run in a system for allocating channels, cause the system for allocating channels to perform the method for allocating channels according to any one of claims 1 to 8.

18. A computer program product comprising instructions for causing a system for allocating channels to perform the method for allocating channels according to any one of claims 1 to 8 when the computer program product is run on the system for allocating channels.